DE1645746A1 - Liquid fuels - Google Patents

Description

FARBWERKE HOECHST AG. formerly Meister Lucius & Brüning file number: P 16 45 746.8 - Fw 5203a

Date: March 3, 1969
Dr.Gr/zdl

Liquid fuels

The invention relates to liquid fuels, especially oily hydrocarbons, such as. B. bunker oil, heating oil, diesel oil and The like, to prevent storage vessels or transport facilities as a result of the inevitable presence Corrosion damage occurring in different amounts of water contain additives of organic inhibitors.

From the German Auslegeschrift 1 090 486 it is already known as a corrosion protection agent amide-carboxylic acids or their Use salts. In practice, those that are soluble in oil and water have proven to be particularly suitable for use in liquid fuels Amine salts of these amide-carboxylic acids introduced. These salts the However, amide-carboxylic acids do not meet the high requirements in practice with regard to corrosion protection. They also have the disadvantage that they are in the presence of small amounts of water cause the formation of pasty emulsion flakes in the liquid fuels, which in turn cause sensitive disturbances such as Burner and filter blockages in the heating systems.

It has now been found that when using liquid fuels a significant improvement in the anti-corrosion effect of the known amine salts of amide-carboxylic acids is achieved if one them at least about 20 percent by weight, based on the weight of the amide-carboxylic acids, of salts soluble in oil and water or also non-stoichiometric mixtures of carboxylic acids in general formula

909881/128 5

R-COOH (I),

where R is a hydrocarbon radical with 5 to 20 carbon atoms, which can be saturated, unsaturated, straight-chain, branched or ring-shaped, means adding, where the acid or Amine components can also be present in excess.

The present invention thus relates to liquid fuels with a content of salts soluble in oil and water or else non-stoichiometric mixtures of primary, secondary or tertiary amines and amide-carboxylic acids of the formula

R -CN-CH- (CH ₀ ) - COOH (II) χ ι ,,, δ η

^{0 R} 2 ^R 3
and carboxylic acids of the Foraei

R-COOH (I),

wherein the two acids are present in a weight ratio of about 80:20 to about 20:80. In the formulas, R ₁ denotes a hydrocarbon radical with 8 to 23 carbon atoms, R "denotes hydrogen, an alkyl, hydroxyalkyl or phenyl group, preferably a lower alkyl radical with up to 4 carbon atoms, in particular the methyl radical, R ₃ denotes hydrogen or a lower alkyl radical and η 0 or 1; R has the meaning given above.

Non-stoichiometric mixtures of amines and the acids of the formulas (I) and (II) which can be used are those in which the amine or acid components are present in an excess of up to 50 % over the amounts required for neutralization. It is preferred to use mixtures which have an excess of amine.

9 0 9 8 8 1 IA 2 8 5

16457 ^ 6

In the case of liquid fuels with a content of the specified anti-corrosion agents according to the present invention, the The risk of the formation of the disadvantageous pasty emulsion flakes mentioned above with small proportions of water is excluded or at least considerably reduced.

In the case of the anti-corrosive agents according to the invention composed of amines and acids of the formulas (I) and (II), a suitable choice is made Components to ensure that products soluble in oil and water are obtained. To achieve oil and water solubility in To achieve the same level it is z. B. appropriate when using longer-chain carboxylic acids with more than about 14 carbon atoms relatively short-chain hydrophilic amines, such as. B. use isopropanolamine as a salt-forming component. on the other hand can when using acids with shorter carbon chains, preferably a longer-chain hydrophobic Arain, such as coconut oil or cyclohexylamine can be used.

Carboxylic acids of the formula (I) for the corrosion inhibitors according to the invention are, for example: caprylic acid, Capric acid, coconut oil fatty acid, coconut oil first-run fatty acid, Oleic acid, soybean oil fatty acid, gas oil naphthenic acid, and fatty acid mixtures with unbranched ones obtained by paraffin oxidation and branched alkyl chains, for example from 7 to 11 carbon atoms. As carboxylic acid components that are used with an Arain to Salt can be combined, in addition to single carboxylic acids, mixtures of carboxylic acids of the type mentioned, preferably those of 6 to 12 carbon atoms, such as those contained, for example, in coconut oil precursor fatty acid, can be used.

Examples of primary, secondary or tertiary amines are: hexylamine, cyclohexylamine, isopropanolamine, l-amino-3-isopropoxypropane, Diethanolamine, morpholine, N-methyldiethanolamine, N-benzyl diethanolamine, Ν, Ν-dimethyl-cyclohexylamine and Diethylaminoethanol.

909 881/1285

From the range of acids of the formula (II), as they are preferably used, there may be mentioned, for example: oleoyl sarcosine, Lauroyl sarcosine, N-oleoyl-N-methy1-ß-aminopropionic acid.

The concentration in the liquid fuels according to the invention Corrosion inhibitors used can be about 0.0001 to 0.5 percent by weight, preferably 0.001 to 0.05 percent by weight, be.

The excellent anti-corrosion effect of the additives according to the invention, consisting of amines and acids of the formulas (I) and (II), which is superior to such inhibitors, besides the arain component contain only acids of the formula (II) alone are shown by the examples listed in the table below:

909881/128 5

Reduction of corrosion

example

Additive dissolved in EL fuel oil

concentration
Wt%

Proportion of the area covered with rust (in tenths after 24 h)

no addition

10

Cyclohexylamine salt of N-0.002 oleoyl-N-methyl-aminoacetic-0.005 acid O, oil

4 2 O

Cyclohexylamine salt of a 0.002 mixture of equal parts by weight 0.005 parts by weight of a synthetic 0.01 table first run fatty acid ¹ ^ and N-oleoyl-N-methylaminoacetic acid

0 0 0

Cyclohexylamine salt of a mixture of equal parts by weight of a synthe = ·. Table top fatty acid ¹ ^ and N-oleoyl-N-methylaminoacetic acid mixed with an excess of free cyclohexylarain of 50%, based on the amount required for neutralization

0.002 0 0.005 0 0.01 0

Morpholine salt of a mixture of 75% coconut fatty acid and 25% N-oleoyl-N-methyl-ßaminopropionic acid

0.002 1 0.005 0 0.01 0 0.002 2 0.005 1 0.01 0

N-benzyl diethanolamine salt a mixture of 75% caprylic acid and 25% N-lauroyl-N-methyl-aminoacetic acid

1) Acid mixture produced by paraffin oxidation with straight-chain and branched alkyl radicals with essentially 7 to 9 carbon atoms.

90 9 881/12 0S

The test of the non-inhibited oil according to Example 1 and the The substances listed in Examples 2 to 6 are based on the static water drop test by H. R. Baker, D. T. Jones and W. A. Zisman, Ind. Eng. Chem. 49, 137 (1949) in the following way;

Equilateral triangles made from deep-drawn sheet metal were used as test sheets St VI1 / 23 with an edge length of 45 mm, the corners of which are sloping downwards were bent so that the sheets came to stand horizontally about 4 mm above the base. In the middle of the triangle was a circular recess 19 mm in diameter and 2.5 mm deep. Each test panel was thoroughly tested before use sanded, degreased with benzene and placed in a 250 ml beaker. The inhibitor to be tested was in the in the respective Example given concentration dissolved in heating oil EL. Then 100 ml of this solution with 0.5 ml Shake 0.5% aqueous sodium chloride solution vigorously and leave to stand for a few hours to allow the aqueous phase to settle. Then 60 ml of the oily solution were first placed in the beaker with the test plate and then 0.25 ml of the again The settled aqueous saline solution is poured into the recess of the test panel. Eventually the experimental approach was in the dark stored at room temperature. The tests were evaluated by visual determination of those formed after 24 hours Amount of rust. When using non-inhibited EL heating oil (Example 1), the test panel was indented after just 24 hours completely covered with rust.

A comparison of Examples 3 to 6 with Example 2 leaves the. recognize superior improvement in corrosion protection achieved by Use of a mixture of acids of the formulas (I) and (II) in Compared to the sole use of an acid of the general formula (II) in combination with amines is achieved.

909881/1285

Claims (3)

16457 * 8 claims 1. Liquid fuels, characterized by a content of salts which are soluble in oil and water or which are non-stoichiometric Mixtures of primary, secondary or tertiary amines and amide-carboxylic acids of the general formula R ₁ - C - N - CH - (CH ₀ ) - COOH (II) J- ti ι t ^{Δ η} 0 R ₂ R ₃
and carboxylic acids of the formula R-COOH (I), in which R is a hydrocarbon with 5 to 20 carbon atoms, R _{1 is} the radical with 8 to 23 carbon atoms, R is hydrogen, an alkyl, hydroxyalkyl or phenyl group, preferably a lower alkyl radical with up to 4 carbon atoms, in particular the methyl radical, R ₃ Hydrogen or a lower alkyl radical and η denotes 0 or 1, the acids of the formulas (I) and (II) being present in a weight ratio of about 80:20 to about 20:80. 2.. Liquid fuels according to Claim 1, characterized in that that the proportion of additives is about 0.0001 to 0.5 percent by weight, preferably 0.001 to 0.05 percent by weight. 3. Liquid fuels according to Claims 1 and 2, characterized in that that in the additives the amine component in an excess of up to 50%, based on the salt formation required stoichiometric amount is present. 909881/1285